Antifouling activity of crude extracts from some Red Sea soft corals

En The antifouling activity of crude extracts of 5 common Red Sea soft corals was examined. The extracts were mixed with a marine paint, applied to PVC panels immersed in the seawater of Suez Bay (Red Sea). The barnacle Balanus amphitrite (Crustacea) and tube worms Hydroides elegans (Polychaeta) are the dominant fouling organisms in this area. The results demonstrated that all the tested soft coral extracts exhibited significant antifouling activities with varying degrees. Extracts of Sinularia heterospiculata and Sinularia variabilis showed the highest and potent wide spectrum antifouling activity, particularly in the first 17 days of fouling formation. Extracts of Sinularia polydactyla exhibited significant selective inhibition against settlement of barnacle, while the extracts of Lithophyton arboreum showed significant antifouling activity against the latter successional stages of tube worms. The results of the current study propose that these soft corals may contain bioactive compounds with antifouling activity. These bioactive molecules can be isolated, purified, identified and chemically synthesized for commercial uses in the development of nontoxic and environmentally acceptable antifouling coatings